Straining device for vacuum drying apparatus



Mgrch 4, 1930. i A. E. JONSSON STRAINING DEVICE FOR VACUUM DRYING APPARATUS Filed March 21. 1 928 2 Sheets-Sheet l ATTORNEYS.

March 4, 1930. A. E. JoNss'oN v STRAINING DEVICE FOR VACUUM DRYING APPARATUS Filed March 21, 1928 2 Sheets-Sheet 2 I mill.

Patented Mar. 4, 1930 PATENT OFFICE AUGUSTINUS EDVARD JONSSON, OF LIDINGO, SWEDEN 'I'RAINI NG DEVICE FOR VACUUM DRYING APPARATUS Application filed March 2 1,- 1928, serial No. 263,352, and in Sweden April 9, 1927.

The present invention relates to vacuum drying apparatus provided with arotating or oscillating drying drum, the principal obj ect of the invention being to provide a straining device having means for automatically cleansing the straining apertures, the dry ng drum of the apparatus communicating through said straining device with the vacuum generating source.

The straining device forming the subject matter of this application consists of one or more hollow members or bodies attached to the drying drum and having one end'closed, the other end being connected to a vacuum pump. The members or bodies are provided along their circumference with one or more sets of straining slots, which may extend along the whole circumference of the member or body, or only over a part of it. The slots may be formed by sawing or cutting the walls of the hollow members and may be disposed in parallelism either perpendicularly to or spirally of the longitudinal axis of the member. In order to prevent the material operated on from choking the slots so as to prevent the proper drawing off of the steam or gases which are developed in the drum during the drying operation, an automatic cleansin device is provided in the form of a hol er adapted to move in'relation to said hollow members or bodies, and which cleansing device is provided with a number of teeth extending into the slots of said bodies, said teeth being adapted, on the rotation of the hollow bodies, to be displaced in the slots by reason of the fact that the tooth holder is maintained by gravity in its position of stable equilibrium.

Other features characteristic of the invention will be hereinafter more fully described in connection with the accompanying drawin in which ig. 1 is a partly sectional end view of an embodiment'of the present invention; I

Fig. 2 is a longitudinal section there,-

through; and l a Fig. 3 is-a side elevation of a drying drum illustrating the straining device arranged therein, the drum being adapted to be given an oscillatory movement by means of a motor or the like,,and which drum is connected by means of flexible hose or tubes with a source of vacuum and with means for supplying hollow body providedwith straining slots 2. y

The body is provided with a flange 3 by means of which it may be attached, for instance, to

one end wall of a vacuum drying drum or cylinder A, as shown in Fig. 3. A holder in the form of a pair of rings 4 mounted for rotation on the hollow body adjacent theopposite end thereof, is provided with teeth 5 carried by cross bars 6 secured at their op posite ends to the ring 4. In the embodiment shown herein, the ends of the cross bars are inserted into a pair of channel members or sleeves 7 which are detachably secured to the ring-4 by means of flanges 9 and bolts 8 thereby to permit the'ready removal of the cross bars when desired. An arm 10 depends radially from each of the rings 4, and between said arm is secured a weight 11 by means of bolts 12.

A flexible pipe 14 may be placed in communication with the hollow body 1 and with a vacuum pump, not shown, whereby the vapors and gases produced. in the drum A may e drawn ofl through the slots 2 of the body 1 and disposed of in any suitable manner.

During this operaton, however, a part of the drying material in the drum A will probably be carried to the slots2,- so that an accumulation of such material would eventually chock said slots. On the oscillation of the drying drum A, however, the body 1 will also be oscillated. At the same time, the

, holder 4, by reason of the counterbalancing weight of the member 11, will be held stationary, so that the relative movement between the teeth 5 and the slots will clear the same of any of the materialand'prevent accumulation thereof.

In order to facilitate the'removal of par- A ticles which may possibly have entered the slots 2, the working faces of the teeth 5 are,

as shown in Fig. 1, preferably inclined, whereby the teeth at-the same time they dislodge the material cperipherically from the slots, will also force it' tomove radially of the hollow member. The material to be dried is introduced into the drum A as well as removed therefrom after drying through the openings 15, which are closed by means of covers. m,

It will be understood that the device above described is intended merely as one embodiment of the invention, which may be applied in other ways without departing from the spirit and scope of the appended claims.

For instance, the drum A might be given a continuously rotating movement instead of an oscillating movement. In that case, however, the pipes between the source of vacuum and the heating source and the drum would necessarily have to be provided with connections for permitting such continuous rotation. a I claim: l. A device of the character described,

comprising in combination, a movable support, a straining device comprising a hollow body mounted in said support for movement therewith and connected to a source of vacuum, said body being provided along its circumference with straining slots, and an automatic cleaning device mounted to move in relation to the hollow body during movement of the support and provided with cleansing teeth extending into said slots, the organization being such that on the movement of the support said cleansing device will maintain its stable equilibrium whereby said teeth are displaced in the slots. 2. A device of the character described, comprising in combination, a rotatable support, a straining device comprising a hollow body mounted in said support for rotation therewith and connected to a source of vacuum, said body being provided along its circumference with straining slots, and an eccentrically loaded cleansing device mounted for rotation about said hollow body and provided with cleansing teeth extending into said slots, whereby on the rotation of the support said cleansing device will maintain its stable equilibrium and said teeth will be displaced in the slots.

3. A device of the character described, comprising in combination, a rotatable support, a straining device comprising a hollow body mounted in said support, for rotation therewith and connected to a source ofvacuum, said body being provided along its circumference with straining slots, and an au- -tomatic cleansing device mounted to move in relation to the hollow body and provided with cleansing teeth extending into said slots, the organization being such that on the rotation of the support said cleansing body will maintain its stable equilibrium whereby said teeth are displaced in the slots, the working faces of said teeth being inclined.

AUGUSTINUS EDVARD J ONSSON. 

